1. Technical Field
The present invention relates to an adaptor for connecting a microstrip line and a waveguide.
2. Description of the Related Art
An adaptor for connecting a microstrip line with a waveguide may be used to provide the signals of the microstrip line to the waveguide or provide the signals of the waveguide to the microstrip line.
For example, an adaptor can be used when signals received at a radar antenna implemented in the form of a microstrip line are to be provided to a waveguide or when the signals of the waveguide are to be provided to a radar antenna implemented in the form of a microstrip line.
FIG. 1 is a cross-sectional view of a typical adaptor for connecting a microstrip line with a waveguide according to the related art, FIG. 2 is a perspective view of a typical adaptor for connecting a microstrip line with a waveguide according to the related art with the upper portion removed, and FIG. 3 is a perspective view of a typical adaptor for connecting a microstrip line with a waveguide according to the related art as seen from below.
Referring to FIG. 1 through FIG. 3, an adaptor according to the related art may have a waveguide part 110 (FIG. 1) joined to an upper portion of a microstrip line part 100 (FIG. 1) and may have a termination member 120 (FIGS. 1, 3) joined to a lower portion of the microstrip line part 100 (FIG. 1).
In FIG. 2, the microstrip line part 100 (FIG. 1) has a microstrip pattern formed on a substrate, and includes a microstrip port 200, for connecting to another microstrip device such as a microstrip antenna, etc., and a probe 202, for coupling to a waveguide. A ground conductor 204 may be formed in other areas of the substrate with a particular distance separated from the port 200 and probe 202.
Referring to FIG. 3, the lower portion of the substrate in the microstrip line part 100 (FIG. 1) can have a ground conductor 206 formed in all areas other than the area where the termination member 120 is joined.
In FIG. 1-3, the waveguide part 110 may be joined to an upper portion of the microstrip line part 100, and the ground conductor 204 may not be formed in the area where the waveguide part 110 is joined.
The signals of the microstrip line part 100 may be provided from the probe 202 to the waveguide part 110. The waveguide part 110 may be structured to have a waveguide hole formed therein, and the signals of the microstrip line part 100 may be transmitted through the waveguide hole.
The termination member 120 joined to a lower portion of the microstrip line part may be closed at the bottom and may have a hole having the same size as that of the waveguide part 110.
The termination member 120 may function such that the signals provided from the probe 202 are suitably coupled to the waveguide part 110. That is, the termination member 120 may function such that the signals from the probe 202 are provided to the waveguide part 110 on the upper portion of the substrate and are not coupled to the lower portion of the substrate. The termination member 120 may have a length that is a quarter (¼) of the wavelength corresponding to the operating frequency.
Thus, an adaptor for connecting a microstrip line and a waveguide according to the related art can be structured to have a waveguide part 110 and a termination member 120 joined to the upper and lower portions of a microstrip line part, respectively.
With an adaptor according to the related art having the structure described above, it may be difficult to join another substrate onto the substrate of the microstrip line part 100, and even if another type of substrate (e.g. a substrate having a circuit formed thereon) is joined, it may be difficult to suitably implement coupling of signals.
Thus, with an adaptor based on the related art, it may be necessary to include the microstrip line part as a single layer, and it may be difficult to implement the microstrip line part in multiple layers.